The present invention relates to a fuel injection pump of a distribution type for delivering fuel to the combustion chambers of an internal combustion engine and, more particularly, it relates to a distribution type fuel injection pump capable of electrically controlling the fuel injection timing and/or the injection ratio characteristics.
This distribution type fuel injection pump is disclosed by Japanese Patent Disclosure No. 148051/57. This well-known fuel injection pump is provided with an electromagnetic valve for controlling the amount of fuel injected, and is located in the suction passage through which fuel is supplied to the pump chamber so that it opens and closes the suction passage to control the amount of fuel sucked into the pump chamber, and therefore, the amount of fuel injected. More specifically, the electromagnetic valve is of the usually-closed type and the amount of fuel sucked into the pump chamber can be adjusted by controlling the time period during which the electromagnetic valve is opened. When the electromagnetic valve is employed, therefore, the amount of fuel injected can be controlled electrically.
In a case where the fuel injection timing and/or the injection ratio characteristic are to be electrically controlled, however, various matters still prevent an effective fuel injection pump from being provided. Accordingly, there has been demanded a distribution type fuel injection pump capable of effectively and electrically controlling the fuel injection timing and/or injection ratio characteristics.